db: Migrate "message" APIs to enginefacade
db: Migrate "message" APIs to enginefacade

Migrate message-related APIs from the legacy enginefacade to the
modern context-based enginefacade.

Change-Id: Id9eae8fff3d8804ec587f888c9909283de5b3c95
Signed-off-by: Stephen Finucane <4725dc7f3632bf126d9fbdc30c347e91e8d2fe16@redhat.com>

openstack/cinder,openstack/cinder,mahak/cinder,mahak/cinder